dna deoxyribonucleic acid. the structure of dna (deoxyribose nucleic acid) a. dna is a...
TRANSCRIPT
DNA DeoxyriboNucleic Acid
The Structure of DNA (DEOXYRIBOSE NUCLEIC ACID)• A. DNA is a macromolecules
called NUCLEIC ACIDS. The other type of molecule in this category is RNA.
Remember…
• Since DNA is a macromolecule (POLYMER), it is really made of many (in this case billions) smaller molecules (MONOMERS!) put together. The DNA monomer is the individual NUCLEOTIDE.
Nucleotide•A single piece of the DNA strand
•Made of 3 parts▫Deoxyribose (sugar)
▫Phosphate▫Base (A,G,C or T)
Purines Pyrimidines
Adenine
Guanine Cytosine
Thymine
Phosphate group
Deoxyribose
DNA Nucleotides
The backbone of 1 strand
•Alternates between the sugar (deoxyribose) and the phosphate group
•The base sticks out into the middle
Double-Stranded•The bases hydrogen bond
with each other to hold the strands together
•The base from one strand bonds with the base from the other forming a complementary base pair
a. ADENINE bonds with THYMINE
b. GUANINE bonds with CYTOSINE
•They coil into a double-helix
Hydrogen bonds
Nucleotide
Sugar-phosphate backbone Key
Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)
Figure 12–7 Structure of DNA
Section 12-1
DNA Structure•Theorized to be a double helix consisting of 2 strands wrapped around each other
•Discovered by Watson and Crick AND Rosalind Franklin
Rosalind Franklin
•Provided the scientific evidence that allowed Watson and Crick to suggest the double helix
•But often does not receive credit and since she had died – couldn’t share in the Nobel prize
• What about the structure of DNA makes us unique???
ORDER OF BASE PAIRS
The Structure of RNA
A. RNA is made of a SINGLE strand of NUCLEOTIDES. Each of these is composed of:
1. NITROGENOUS BASE2. SUGAR (RIBOSE)3. PHOSPHATE
i. RNA also has 4 possible nitrogen bases BUT instead of thymine, RNA has a nitrogen base called URACIL.
What You Should Know about DNA structure
•The basic structure of a nucleotide
•The basic structure of DNA•How DNA and RNA differ•Base-pair rules•How the structure suggests a replication method
Genetic disorder projects•Find 4 people to work with then find a computer
and log on.•Once you have your disease start researching it.•Before you leave: Divvy up the work AND
SHARE EMAIL & phone numbers so you can contact each other.
•Next class you have time to work on the project. Your HW is prepare for this time together as it is the ONLY class time you will be given. Have your portion COMPLETE!!!
•The final project MUST BE EMAILED TO ME by:•A day- 2/24 9:30 pm•B day- 2/25 9:30 pm
2/21-2/24
•DNA Jewelry (~45 minutes)•Genetic presentation project (~40 minutes)
•HW: final presentation due to my email ▫A day- 2/24 9:30 pm▫B day- 2/25 9:30 pm